That was a world war against global powers. There was the very real possibility that the United States would have been invaded. People didn't mind sacrificing and there was an expectation that at some point things would end and society would return to normal. The current enemy is a tiny, unseen force who's primary weapon is fear through attacks on the populace. How can the government ever claim that this enemy has been defeated if it can't even be seen? At what point do security measures get relaxed? In my opinion, the war against terror will be never ending. It's up to the citizens to make sure that government doesn't overstep the constitution in it's quest to protect the public.
And the WOT is a "world war against global powers". The fact they don't wear a military uniform, but the uniform of a religion.
"The current enemy is a tiny, unseen force" .. I don't agree with your assessment that the terrorists are "tiny" or "unseen". These people are in 70 nations - that's not "tiny". And .. everywhere they go DEATH follows .. that's not "unseen".
While the WOT will not have an ending as in the past - where there is surrender - it will be neutered to the point that people will begin to realize this is NOT a major issue anymore. I believe it can reach this point. How long it will take .. I don't have that answer .. but you're right .. we - the citizens - have to make sure that we are protected but not denied our Constitutional rights.